Retrieving Your External IPv4 Address

TYLER MONROE Updated by TYLER MONROE

Beginning January 2026, the IRS requires that e-filed 941 and 94x forms (940, 943, 944, 945, etc.) include the user's IP address in the submission file. Payroll System will attempt to determine your IP address automatically when the file is created. Firewalls, anti-virus software, or virtual private networks (VPN) may block it from automatically obtaining it. If so, Payroll System will prompt you to input your IP address manually.

The IP address will look like a series of numbers like this: 192.0.43.10

Websites that will look up a computer's external IPv4 address

There are numerous websites that perform this service; CFS does not make any recommendations. Some examples are provided:

How did we do?

Requirements to E-File Forms 94x (941/940/943/944/945)

Signature Methods

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